Christchurch City Council has included living roofs in their Draft Christchurch Central City Plan. It is proposed to encourage living roofs and walls in the Central City through demonstration projects, incentives and best practice guides.
Whilst there is no direct legal requirement to provide a green roof in New Zealand there may be an indirect requirement as mitigation for impact on an areas amenity, stormwater amelioration or on protected species. Waitakere City Council (now Auckland Council) has produced a green roof information pack and is leading by example having installed a living roof on their Henderson Council building. Auckland Regional Council, now Auckland Council, is promoting living roofs through their technical publication 10 as a sustainable drainage option.
Unfortunately we are lagging behind our overseas counterparts. A number of cities in the United Kingdom, US, Canada, Germany, China, Austria, Switzerland and Japan promote green roofs via a combination of legal frameworks, financial grants and policy incentives. Germany has installed about 130km2 of living roofs and is installing them at a rate of approximately 13km2 every year.
In New Zealand we should see our rooftops as an underutilised asset. New and existing rooftops should be seen as a very real opportunity to help us adapt to climate change. Unless we secure high quality environments for people and wildlife, the quality of our cities will decline – especially as the effects of climate change begin to take hold.